Drifting valve



V. P. MCVOY.

DRIFTING VALVE.

APPLICATION FILI-:D Ivi/III. so, I92o.

LASQQC i I Patented Jan. 10, 1922,

3 SHEETS-SHEET 2.

L/ INV EN TOR.

A ATTORNEY.

V. P. lVlcVOY.

.DR'IFTINGVALVB APPLICATION FILED IIIIAII. so, Iszo.

LISQ., Patented Jan. 1091922* 3 SHEETSf-SHEET 3.

VINCEN P. MCVOY, OF MOBLE, ALABAMA, ASSIG-NOR TO UNTED STATES RAILW'AY SUPPLY COMPANY, OF DOVER, DELAWARE, A CORORATION OT? DELAWARE.

DRIFTING VALVE.

Application filed March 30, 1920.

.To all whom t may concern .Be it known that I, VINCEN P. MoVoY, a citizen ot thc United States, residing at Mobile, in the county ot Mobile and State or Alabama, have invented certain new and usei'ul improvements in Drifting` Valves, of which the following is a specification.

This invention relates to certain new and useful improvements in what are known as drifting valves tor locomotives and while the present invention is along the same gcneral line as prior devices of this nature devised by me, one otl which, for instance, may be seen in Patent No. 1,229,993, dated dune 12, 1917, it is to be understood that the novel features hereinafter disclosed and claimed are not necessarily coniined to their association with the details ot construction in other respects disclosed in said patent, but are applicable to other iorms ot' dritting valves with which they may be associated.

rihe present invention has 'for its object-s among` others to provide an improved dritting' valve ot the general character disclosed in my said patent whereby the valve hitselt, is provided with means tor creating a vacuum.

The present invention has for a further object to provide simplified means for accomplishing' this object.

This can be accomplished in a variety of ways. some of which l have herein illustrated, but it is to be understood that the invention in its broad sense is in no wise restricted to such particular forms of construction.

Other objects and advantages ot the invention will hereinafter appear, and the novel tea-tures there-ot will be particularly pointed out in the appended claims.

rlhc invention, in such forms as at the present time appear to be the preferable ones. is clearly illustrated in the accompanyinn drawings, which, with the numerals et reference thereon, term a part ot this s'iccitication, and in which- Figure 1 is a substantially central vertical section through my improved valve.

Figure 2 is a similar view showing a vhtly modified form.

Figure 3 is a view similar to Figure 1, showing the relation ot the parts when the falve is open.

Specification of Letters latent.

Patented Jan. itl, Serial No. 369,880.

Like numerals of reference indicate like parts throughout the different views.

Referring to t-he drawings,

1 designates the body portion ot the valve, 2. the cap or head thereof secured in position in any suitable way.

3 is a lower portion preferably substantlally cone-shaped, as shown, with a dependingl cylindrical portion 3a. i

The body portion has upon diametrically opposite sides extensions 1a, 1b, for suitable connection with the union members 4 and la, respectively, the former designed Jfor connection with the boiler and the latter .tor connection with the engine. any suitable form oi" union connection may be employed.

5 is a steam piston fitted to reciprocate within the upper cylindrical portion ot the body 1 oil the valve, havingl suitable packing,` rings, as shown. The said piston is provided between its upper and lower faces with an annular space or channel 6 which connects upon one side by suitable passage 7 with. the space or chamber 8 and upon the other side by means ot an upwardly extending' passage 9 with the chamber 10 above the piston. The annular passage 6 communicates by' means ot the lateral ports 11 with the chamber 12 in which is designed to reciprocate the pilot valve 13 the aimular walls of which control the exit from these ports.

14 is a spring' bearingon the upper end oi' the diiierential steam piston and disposed within the chamber 1() and acting to assist in holding the said piston in its downward position. This spring, however, is not absolutely essential and it may be omitted without detriment to the successtul operation of the valve.

15 is a check valve carried by the difierential piston and adapted to a seat 16. as clearly shown in Figure 1. As will be readily understood upon reference to Figure 1, the members 5 and 15 are toi-med separately, the Jformer being" cast iron and the latter of some other suitable material such as nickel bronze, the two parts being connected together as one by means ot' the nut 16 which has threaded engagement with the member 15 and bears against the adjacent end of the member 5, as clearly shown.

17 is a spring interposed between the outer end of the nut 16 and the pilot valve 13 and tending to hold the latter to its seat, although this spring may be omitted without detriment to the successful operation oic the device.

The seat 16 for the valve member' 15V is formed separate and screwed into the opening in the division plate 18, as seen clearly in Figure 1, its flange 19 bearing against a shoulder 20 for an obvious purpose.

21 is the stem of the pilot valve. It is guided in the portion 15 and at its lower end guided by a suitable guide 22, in the present instance shown in the form of a bushing held in the nut 23 in the bottom wall 24 of the body portion of the valve.

25 are bolts passed through -langes on the portion 24 of the body of the valve and the upper end of the lower portion 3 ior securely holding the saine together.

The stem 21 of the pilot valve is provided f with longitudinal flutes or channels 26 which are always in communication with a counterbore or chamber 27 in the lower end of the portion 15 of the piston. The pilot valve is adapted to a seat 28 at the lower end of the chamber 12.

The depending or skirt portion 29 oit the member carrying the seat 16 is provided with a pluralityT of openings 30 communicating with the chamber 31 beneath the division plate 18, these openings being normally closed by means of a ring 32 carried by the member 15, there being a space 33 surrounding the lower portion oi the member 15 and communicating with the chamber 8 when the check valve is unseated and thence communicates with the chamber 31 through the openings 30 beneath the ring 32 when the valve is unseated to produce a gradual opening.

34 is a vacuum and pressure piston movable in the chamber formed in the lower portion 3 and having a depending or shirt portion 35 adapted to reciprocate Vin the chamber 36 formed in the depending` portion 3, as clearly seen in Figure 1. `This depending portion 35 is provided with a plurality of openings 37 adapted to communifate with the atmosphere through openings 33 through the wall of the depending portion 3 when the piston 34 is raised to bring the openings 37 into communication with the chamber 42.

39 is a check valve in the upper end of the chamber 40 formed in the depending portion olf the vacuum and pressure piston and adapted to open upward. This valve controls a passage 41 communicating with the space 42 beneath the vacuum and pressure piston in the lower portion 3 of the valve.

The passage 41 communicates with the space 43 above the check valve, this space allowing the requisite upward movement of said check valve, as will be hereinatter eX- plained.

44 is a passage or channel formed in the wall ofthe body portion 1, this channel communicating with an annular space 45 around the nozzle portion 46 which is threaded into the neclr 47 extending from the body portion 1 and this annular space 45 Vhas leading therefrom the ports 48 which,

in turn, communicate with the annular space 49 surrounding the inner nozzle portieri 50 which is also received in the neel: 47 and retained in place by the nozzle portion lt is to be noted that the annular space 49 communicates with a space 51 between the bores of the nozzle portions 46 and 50.

52 is the outer portion of the nozzle, the same serving also as a jamb nut, being threaded into the neck 47 and bearing against the nozzle portion 46. llhe bores of the nozzle portions 46 and 52 are inversely tapered, as seen at 53 and 54, respectively, in Figure 1. it will also be noted that the bore of the inner nozzle portion 50 is tapered inversely to the taper 53 ot the intermediate nozzle portion 46.

"With the parts constructed and arranged substantially as hereinbefore described and with the device in position, in practice the drifting valve is affixed in position and the opening 38 connected with a pipe which is designed to extend below the running board of the engine to take care ein' the exhaust from the chamber 42 and also to taire care of the condensation and to admit air to said chamber through the check valine 33 so as to permit upward movement of the vacuum piston by the pull olt the nozzle through the vacuum channel 44. lt is to be noted that the vacuum and pressure piston is provided with a comparatively minute equalizing passage 55 say of one-sixteenth inch diameter to equalize the pressure upon both sides oi said piston, that is the throttle presssure.

lt will also be noted that the depending portion 35 of the said piston 34 is provided -with a drain opening 56 say ot one thirtysecond inch diameter for drainage ot water of condensation `from the chamber 42.

The operation is as follows:-lt is to be understood, et course, that theextension 1 is connected with the boiler and the extension 1b connected with the engine7 or engines, through the medium of the Vunion members 4 and 4a, respectively, so that when steam is turned on to the drifting valve, the said steam will enter through the connection 4 1 into the space 8 above the division portion 18 and through the equalizing hole 7 into the annular channel 6 and thence through the upper equalizing hole 9 intothe space 10 upon the upper side of the steam piston and also into the space above the pilot valve, the steam serving to hold the steam piston and the pilot valve firmly against their seats under boiler pressure.

It is to be understood that'an engine has to use some throttle pressure before it has momentum enough to drift; the throttle pressure backs up through the member da and through the nozzle mechanism hereinbefore described and through the vacuum channel da into the chamber or space 2a and also into the space 3l below the steam piston and into the chamber 42 below the vacuum and pressure piston 34, all equivalent to throttle pressure, and when the throttle is shut ofin for the purpose of allowing the engine to drift or move without throttle pressure, the moving pistons of the engine consume the steam in the said spaces or chambers 24; and 31. The throttle pressure in the chamber 42 which is stored beneath the vacuum and pressure piston 34E now eX- pands, by means of the release of the pressure above it, moving the vacuum and pressure piston 3a upward, and at the 'same time carrying the stem of the pilot valve with it, which causes said pilot valve to move upward uncovering the ports ll, 'thus allowing of the exhaust of the steam from above the steam piston through the ports 9, annular channel (l and ports ll, through the flutes in the stem of the pilot valve into the bore 27 and thence into the chamber 3l and out through the nozzle to the engine. rllhis reduces the pressure in the space above the steam piston, making` the pressure in the chamber 28 greater than that in the space above the steam piston, thus causing` the steam piston to raise from its seat, permitting steam to pass through the chamber' 3l, through the space 33 and the ports 30, and out through the nozzle to the engine with sufficient velocity to produce a vacuum between the nozzle portions and #i6 whicii acts upon the upper side of the vacuum and pressure piston 34C through the vacuum channel 44;, producing suiicient vacuum to hold the drifting valve open until the engine comes to a stop or the throttle is again opened.

rllhe nozzle is so arranged that it will produce from one and one-half to two and onehalf inches vacuum through the vacuum channel all on the vacuum piston Sil suiiicient to exhaust steam under constant pressure to `the cylinder er cylinders not exceeding five pounds.

lt will be clearly understood that the faster the engine is moving, the freer the opening` through the member la and thus there will be delivered a greater quantity of steam to the engine under last movement than under slow movement, for as the engine begins to come to a. stop the pressure in the delivery pipe through the member il will gradually destroy the vacuum that is produced by the two nozzles, which will interrupt the vacuum in the space 24, which causes the vacuum and pressure piston and the steam piston to assume their normal positions, which closes the valve and the engine stops. rI'he valve remains in this position while the engine is under throttle pressure and also while idle.

From the foregoing it will be clearly undei'stood that this drifting valve produces its own vacuum, operating instantly and preventing any partial formation of vacuum and thus producing a perfect drifting valve which will drift an engine to a complete stop and shut off accurately automatically.

As before stated, the invention is capable of embodiment in a variety of forms. In Figure 2 l have shown one of such modified forms of embodiment, in which the vacuum channel 57 instead of being formed as a passage through the wall of the body portion of the valve is formed of a separate tube held at one end in the bottom wall of the body portion l of the valve and its ether end expanded or otherwise held in a portion of the nozzle 58. rlhe purpose and function are the `same as in the form illustrated in Figure l.

ln the event that the throttle is shut off and then opened suddenly and shut olf again so as to destroy the pressure in the chamber i2 beneath the valve Se and failing to start the valve in operation, then it would be necessary for the engine to create a partial vaeuum instantaneously, thus pulling the piston 34C upward, and then the valve 39 serves its purpose of admitting` air through the opening 8S into the space 3G and into the chamber 40, lifting the valve 39 and allowto flow through the passage 411 into ingair duced the space 42 to destroy the vacuum pr on the under side of the piston 341i-,

h/.ledilications in detail may be resorted to without departing from the spirit of the invention or sacrilicing any of its advantages.

lllhat is claimed as new is l. ln a" drifting valve, a steam-controlling valve, a vacuum and pressure piston movable in one direction independent ef said steam-controlling valve. means operated by said piston for controlling the movement of said valve, means for operating said steam-controlling valve, pressure. means confined in said valve for raising said piston, and a vacuum channel and vaeinun-creating means within the valve and affording coininunicatien between the space above said piston and the engine for holding said piston in raised position.

2. ln a drifting valve, a steam-centraliing valve, pressure-operated means mevable in one direction independent ef said steamcentrolling valve for opening the same, a trap fer steam beneath said means, and a vacuum channel and vacuum creating means eonstitut'ug a part of the drifting valve and affording direct cemniunication between the space above the first-named means and the connection with the engine llO and operating in conjunction with the tlow oi" steam to the engine to hold said iirstnamed means in raised position.

3. ln a drifting valve, the combination with a steam-controlling valve, means for operating the same, and a piston movable in one direction independent of said steamcontrolling valve and operable to open position by pressure therebeneath, oi a vacuum channel and vacuum-creating means within the valve and aiiording direct communication between the space above said piston and the connection with the engine for holding said piston in its raised position and means tor trapping steam beneath said piston.

al. ln a drifting valve, asteam piston, a steam-controlling valve, a vacuum and pressure piston movable in one direction independent of said steam-controlling valve and adapted to be raised by pressure stored therebeneath, and a vacuum channel and vacuum-creating means within the valve and affording communication between the space above said piston and the engine for holding said vacuum and pressure piston in open position, means for trapping steam beneath said piston, and means whereby the steamcontrolling` valve is operated by the raising oi' said piston.

5. ln a drifting valve, a steam piston, a steam controlling valve, a pilot valve, a vacuum and pressure piston adapted to be raised by pressure stored therebeneath, said pilot valve being` controlled by said pressure and vacuum piston, and vacuum-creating means in thevalve acting in conjunction with the iiow ot steam to the engine for holding said vacuum and pressure piston and pilot valve in raised position.

6. A drifting valve embodying a steamcontrolling valve, a piston movable in one direction independent of said steam-controlling valve pressure-operated to raised position, means for trapping steam beneath said piston, and a vacuum channel and vacuum-creating means, including a nozzle affording communication between the space above the piston and the engine to supply steam to the engine for lubrication and to create a vacuum above the piston to hold the same in raised position.

7. ln adritting valve, a steam-controlling valve, a steam piston, a pilot valve movable therein, a pressure and vacuum piston movable independently oit the steam piston and engageable with the stem ot the pilot valve to move the latter, said pressure and vacuum piston being raised by pressure from beneath, and vacuum-creating means within the valve and affording communication be-V tween the space above said piston and the engine for holding the same in raised position.

8, ln a drifting-valve, a steam-controlling valve, a steam piston, a vacuum and pressure piston movable independent thereof by pressure stored Itherebeneath, a pilot valve movable independently of the steam piston and actuated .by movement of the vacuum and pressure piston, a nozzle in the outlet to the engine, and a vacuum channel within the valve aiording communication between said nozzle and the space above the vacuum.

and pressure piston Jfor creating a vacuum to hold the latter in raisedposition.

9. ln a drifting-valve, a steam-controlling valve, a steam piston, a vacuum and pressure piston, a pilot valve movable independently of the steam piston andA actuated by the vacuum and pressure piston, means in the valve for creating` a vacuum above the vacuum and pressure piston to hold the same in raised position, and means for trapping steam beneath said vacuum and pressure piston to initially raise said piston.

l0. ln a drifting-valve, a steam-controlling` valve, a steam piston, a vacuum and pressure piston, a pilot valve movable independently of the steam piston and actuated by the vacuum and pressure piston, means in the valve for creating a vacuum above the vacuum and pressure piston to hold the same in raised position, means for trapping steam beneath said vacuum and pressure piston to initially raise said piston, and means for admitting atm ospheric pressure to the space beneath said vacuum and pressure piston.

ll.v ln a drifting-valve, a steam-controlling valve, a vacuum and pressure piston, a pilot valve movable by said piston, means in the valve for creating a vacuum above the piston and means for trapping` steam beneath the same which, by its expansion, actuates said piston at the beginning of the operation ot the valve.

l2. ln a drifting valve, a valve casing having an inlet and an outlet, a oheclr valve controlling the flow of steam therethrough, pistons upon opposite sides ot said check valve, the lowermost piston being moved to raised position by pressure stored therebeneath, a nozzle in the said outlet, a pilot valve cooperable with the upper piston and check valve, and a vacuum channel through and within the valve from Asaid nozzle to the space above the lower piston, and means i'or creating a vacuum above the lower piston to hold the same in raised position.

13. ln a drifting valve, a valve casing having` an inlet and an outlet, a check valve controlling` the iiow of steam therethrough, differential pistons upon opposite sides of saidv check valve, the lowermost piston being moved to raised position by pressure stored therebeneath, a nozzle'in the said outlet, aV

pilot valve c ooperable with the upper piston and check valve, a vacuum channel through Y and within the valve :trom said nozzle to the space above the lower piston, means for creating a vacuum above the lower piston to hold the same in raised position, and a pressure relief valve operable independently et the upper piston and movable by the lower piston.

le. ln a drifting valve, a `valve casing having an inlet and an outlet, a check valve controlling the i'io'w ot steam therethrough, rential pistons upon opposite sides of said cheek valve, the lowermost piston being moved to raised position by pressure stored therebeneath, a nozzle in the said outlet, a pilot valve cooperable with the upper piston and eheeh valve, a vacuum channel through and within the valve from said nozzle to the space above the lower piston, vacuum creating means, and

a eheel; valve in the lower piston, the lower piston being raised by pressure stored therebeneath and held in raised position by the vacuum created through said channel.

l5. ln a drifting valve, a valve casing having an inlet and an outlet, a cheek valve controlling the flow of steam therethrough, diilerential pistons upon opposite sides o' said cheek valve, a nozzle in the outlet, a pilot valve cooperable'with the upper piston and check valve, a vacuum channel from said nozzle to the space above the lower pis-- ton, a pressure relierc valve operating independently et the upper piston and movable by the lower piston, and a Check valve in the lower piston, the lower piston being raised by pressure stored therebeneath and held in raised position by the vacuum created through said channel.

16. ln a drifting valve, steam-controlling means, combined with pressure means movable in one direction independent of said steam-controlling means acting to move the same in one position, and a vacuum channel and vacuum-creating means within the valve body independent of said pressure means and atording direct Communication between the space above said pressure means and the conneetion to the engine tor holding said pressure means in such position and means for trapping steam beneath said piston.

l?. ln a drifting valve, a pilot valve, a vacuum and pressure piston movable independent oi said pilot valve `lor a portion ot' its upward travel, a steam piston independent thereolf, a pressure-relieving means, and means for opening the latter' by expansion of steam beneath the vacuum and pressure piston and vacuum creating means within the valve casing independent or" the iirstnamed piston and affording direct communication between the pipe leading to the engine and the space above said piston to hold the latter in raised position.

18. ln a drifting valve, a steam controlling valve, a vacuum and pressure piston, pressure means for raising the latter, means whereby tbe expansion oiC steam initially raises said piston, and vacuumcreating means embodying a passage through the casing o the valve independent of said piston and affording direct communication between the piston chamber and the pipe leading to the engine.

in testimony whereof l ailix my signature.

vinoniv r. never.' 

